A second portion of a writing device is caused to penetrate a through-hole of a tubular portion of a pen pressure transmitter, starting from a first end of the second portion of the writing device, and the tubular portion abuts a surface of a first portion of the writing device that faces the second portion of the writing device. When a pen pressure is exerted on the first portion of the writing device, the pen pressure also is exerted on the tubular portion of the pen pressure transmitter abutting the surface of the first portion of the writing device that faces the second portion of the writing device. The pen pressure is transmitted through the pen pressure transmitter to a pen pressure detector disposed at a position spaced apart from the writing device.

A mechanical pencil according to an embodiment includes: a barrel; a cushion spring that has a rear end supported by the barrel; a sleeve that is biased forward in an axial direction by the cushion spring and movable in a direction perpendicular to the axial direction by an impact applied from outside of the barrel in an elastically supported state; a chuck spring that has a front end supported by the sleeve; a chuck that chucks a writing lead for a mechanical pencil; a writing lead tube that is fitted to the chuck and biased rearward in the axial direction together with the chuck by the chuck spring; and a contact sliding part that suppresses movement of the sleeve in the direction perpendicular to the axial direction.

A mechanical pencil includes a barrel extending in a longitudinal direction, a lead-propelling mechanism, a lead reservoir, a side button, and an eraser-propelling mechanism having a helical cam. The lead-propelling mechanism, the lead reservoir, the eraser-propelling mechanism, and the side button are at least partly housed inside the barrel. The lead-propelling mechanism, the lead reservoir, and the eraser-propelling mechanism are prevented from rotating about the longitudinal direction relative to one another and relative to the side button, and the side button is prevented from rotating about the longitudinal direction relative to the barrel.

A mechanical pencil includes a barrel extending in a longitudinal direction, a lead-propelling mechanism, a lead reservoir, a side button, and an eraser-propelling mechanism having a helical cam. The lead-propelling mechanism, the lead reservoir, the eraser-propelling mechanism, and the side button are at least partly housed inside the barrel. The lead-propelling mechanism, the lead reservoir, and the eraser-propelling mechanism are prevented from rotating about the longitudinal direction relative to one another and relative to the side button, and the side button is prevented from rotating about the longitudinal direction relative to the barrel.

A mechanical pencil and an operating method therefor. A position-based relationship of a tool body is determined by means of the displacement of an adjustment part provided in a sleeve. The tool body has two position-based states, which are retracted and propelled states, and the adjustment part achieves relative stability at the two position-based states by means of a positioning part or a positioning slot in the sleeve, a resetting part, and a control part. The resetting part is driven by the tool body to provide a continuous force to the adjustment part, so that the state of a displacement part on the adjustment part is relatively stable at a retracted position. When the displacement part moves in the positioning slot to a propelled position, the displacement part is limited by the control part, so that the state at the propelled position is relatively stable.

A writing instrument according to an embodiment of the invention including, a chuck that chucks a writing lead, wherein the chuck includes a first chuck pawl which comes into point contact or line contact with the writing lead to press the writing lead so as to apply first contact stress to the writing lead; and a second chuck pawl which presses the writing lead so as to apply, to the writing lead, second contact stress that is lower than the first contact stress, and the first contact stress is configured such that, when a prescribed impact is applied to the writing lead, a contact portion of the writing lead subjected to the first contact stress fractures and absorbs the prescribed impact.

A writing instrument according to an embodiment of the invention including, a chuck that chucks a writing lead, wherein the chuck includes a first chuck pawl which comes into point contact or line contact with the writing lead to press the writing lead so as to apply first contact stress to the writing lead; and a second chuck pawl which presses the writing lead so as to apply, to the writing lead, second contact stress that is lower than the first contact stress, and the first contact stress is configured such that, when a prescribed impact is applied to the writing lead, a contact portion of the writing lead subjected to the first contact stress fractures and absorbs the prescribed impact.

A mechanical pencil including: a body cylinder; a lead releasing unit configured to release a writing lead and having a rear region supported inside the body cylinder such that a front region thereof is flexurally deformable or tiltable inside the body cylinder; and a stretchable elastic body arranged between the lead releasing unit and a body cylinder, in which the lead releasing unit has a pressed portion on an outer circumferential surface of the front region, the body cylinder has a pressing portion in a front region, the pressing portion and the pressed portion abut on each other before the front region of the lead releasing unit is flexurally deformed or tilted, and the pressing portion causes the pressed portion to relatively move to the rear side with respect to the body cylinder when the front region of the lead releasing unit is flexurally deformed or tilted.

A mechanical pencil including: a body cylinder; a lead releasing unit configured to release a writing lead and having a rear region supported inside the body cylinder such that a front region thereof is flexurally deformable or tiltable inside the body cylinder; and a stretchable elastic body arranged between the lead releasing unit and a body cylinder, in which the lead releasing unit has a pressed portion on an outer circumferential surface of the front region, the body cylinder has a pressing portion in a front region, the pressing portion and the pressed portion abut on each other before the front region of the lead releasing unit is flexurally deformed or tilted, and the pressing portion causes the pressed portion to relatively move to the rear side with respect to the body cylinder when the front region of the lead releasing unit is flexurally deformed or tilted.

A second portion of a writing device is caused to penetrate a through-hole of a tubular portion of a pen pressure transmitter, starting from a first end of the second portion of the writing device, and the tubular portion abuts a surface of a first portion of the writing device that faces the second portion of the writing device. When a pen pressure is exerted on the first portion of the writing device, the pen pressure also is exerted on the tubular portion of the pen pressure transmitter abutting the surface of the first portion of the writing device that faces the second portion of the writing device. The pen pressure is transmitted through the pen pressure transmitter to a pen pressure detector disposed at a position spaced apart from the writing device.